US2206549A - Welding apparatus - Google Patents

Description

y 2, 1940- J. E. MCINTOSH ET AL 2,2955% WELDING APPARATUS Filed April 3, 1939 2 Sheets-Sheet INVENTOR. JOHN EDWARD M clNTOSH BY HAROLD UREN 0mm WW ATTORNEYS y 2, 0- J. E. MCINTOSH ET AL 2,206,549

WELDING APPARATUS 'Filed April 3, 1939 2 Sheets-Sheet-Z To ELi LTR GG'S FIG. 3.

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INVENTOR. JOHN EDWARD MclNTOSH HAROLD u EN BY 2:, g Wm ATTORNEYS Patented July 2, 1940 UNITED STATES PATENT OFFICE WELDING APPARATUS tion of Michigan Application April 3, 1939, Serial No. 265,810 In Great Britain September 5, 1938 6 Claims.

This invention relates generally to electrical Welding apparatus and refers more particularly to improvements in welders of the type capable of seam welding the work pieces together.

It is one of the principal objects of this invention to provide a relatively simple inexpensive welder composed of a comparatively few light parts compactly arranged in an assembly rendering it possible to readily manipulate the welder toeffect the desired welding operation.

Another advantageous feature of this invention resides in the provision of a welder of the character set forth in the preceding paragraph rendering it possible to secure the parts together with a continuous seam weld and, in addition, offering the possibility of readily welding sheets having curved or irregular surfaces.

A further object of this invention consists in the'provision of a welder having cooperating electrodes in the form of rolls positioned opposite each other to grip the work to be welded therebetween and having provision for driving one or both of the .rolls to facilitate manipulation of the Welder.

:5 The foregoing, as well as other objects, will be made more apparent as this description proceeds, especially when considered in connection with the accompanying drawings wherein:

Figure 1 is an elevational view, partly in sec- 90 tion, of welding apparatus constructed in accordance with this invention;

Figure 2 is a plan view, partly in section, of the apparatus shown in Figure 1;

Figure 3 is a sectional view taken substantially on the plane indicatgi by the line 33 of Figure 1; p

Figure 4 is a cross sectional view taken substantially on the plane indicated by, the line 4-4 of Figure 3.

J Referring now more in detail to the drawings,

it will be noted that our improved welding apparatus is provided with a bifurcated frame l0 having a hub l I at one end of the furcations thereof and having a cylinder l2 at the opposite end of the same. Sleeved within the hub II is a bushing I3 forming a journal for a spindle I having a roller l5 secured to one end thereof and constituting one electrode of the welding apparatus. The opposite end of the spindle is provided with a reduced threaded portion l6 forming a shoulder l1 adapted to abut the adjacent side of a web I8 formed integral with the bushing l3 and projecting radially inwardly of the bushing. The web I8 is centrally apertured u to receive the threaded reduced portion l6 and a nut I9 is threaded on the reduced portion ID for engagement with the opposite side of the web l8 to cooperate with the shoulder I! in preventing axial displacement of the spindle relative to the sleeve. It is to be noted, however, that the spindle I4 is not fixedly clamped to the sleeve I3 since the electrode or roller I5 is driven by rotating the spindle l4 relative to the sleeve I3.

In the present instance, a portion of the spindle is fashioned to form a worm wheel 20 having teeth adapted to mesh with a suitable worm 2l' journalled in an enlargement 22 of the hub II for rotation e Jcut an axis extending at substantially right angles to the axis of the spindle. The worm 2| is operatively connected to a drive shaft 23 in any suitable manner (not shown herein) and the wall of the bushing I 3 opposite the worm is cutaway sufilciently to permit the desired intermeshing relationship between the teeth on the worm and the teeth on the worm wheel. The drive shaft 23 is preferably of a flexible nature and is operatively connected to an electric motor 24, either directly, or through suitable reduction gearing (not shown herein). In any event, the motor 24 drives the flexible shaft 23 which, in turn, effects the desired rotation of the electrode or roller l5.

Carried by the frame I0 is an arm 25 having one end extending between the furcations and pivotally connected thereto for swinging movement about an axis extending transversely to the axis of the spindle M. In detail, the end aforesaid of the arm is provided with a hub 28 arranged in juxtaposed relation to the hub II on the frame with the axis thereof located in a plane including the axis of the hub II. The hub 26 is lined with a sleeve 21 forming a journal for a suitable spindle 28 and the lower end of the spindle 28 has a roller 29 secured thereto. The roller 29 forms the cooperating electrode of the apparatus and cooperates with the roller l5 in the position of the parts shown in Figure 1 to grip the work A to be welded therebetween. The roller 29 is of greater diameter than the roller i5 and may, or may not be driven.

The upper end of the spindle 28 is secured in the hub 26 in the same manner as the spindle I4 is secured in the hub II and the spindle, together with the hub 26, is pivotally connected to the furcations ill by the studs ill). The arrangement is such as to permit the arm 25 to be swung in a plane, including the axis of the roller l5, in a manner to effect movement of the electrode or roller 29 toward and away from the electrode l5.

Both the electrodes are shown in Figure 1 as being artificially cooled and, for accomplishing this result, both the spindles are axially drilled to form passages 32 communicating with fluid supply conduits 33. The rollers are recessed, as at 34, to'p'rovide jackets for receiving the cooling medium discharging from the lower ends of the passages 32 and the spindles are formed with additional passages 35 through which the fluid medium is exhausted.

The arm 25 is swung about its pivotal connection to the frame it by means of a fluid operated piston 36 reciprocably mounted in the cylinder i2 and normally urged upwardly, or in a direction to swing the rolleror electrode 29 away from the electrode 85 by means of a spring 31. In the present instance, the piston 36 is provided with a centrally disposed hub portion 38 slidably engaging a sleeve lii which, in turn, is fixed on a stud fill and having a radially outwardly extending flange 62 on the lower end forming an abutment for the corresponding end or the hub 38. A coil spring i3 surrounds the hub 38 with the upper end engaging the piston head and having the lower end engaging the flange 42. In other words, the spring 63 acts as acushion and prevents the lower end of the hub 38 from hammering against the flange 62 when pressure is introduced into the upper end of the cylinder H2.

The stud 6i extends below the lower end of the cylinder l2 and is connected to the bifurcated end of the arm 25 by means of a link at. The arrangement is such that when fluid pressure is admitted to the cylinder above the piston 365, the latter is moved downwardly against the action of the springs to abut the lower end of the hub 38 with the flange d2. Inasmuch as the flange 42 is fixed relative to the stud li, it follows that the latter is also moved downwardly with the piston and, due to the connection between the lower end of the stud and arm 25, the latter is swung about its pivotal connection with the frame in a direction to move the electrode or roller 29 toward the cooperating electrode 05.

Fluid pressure is admitted to the upper end of the cylinder 62 by means of a combined switch and valve unit 4! supported on the frame i ii adjacent the cylinder l2 and handle 38. The combined switch and valve W comprises a cylinder 49, sleevedin a bore formed in the frame it, and a piston 5|] reciprocably mounted in the cylinder. The piston 5|] is movable'axially of the cylinder 49 by means of a manually operable control element 56 and is provided with an annular groove 52 in theouter surfaceadapted to communicate with a' fluid pressure supply port 53 in the position of the pistonshown in Figure 3. Also, in the above mentioned position of the piston, the annular groove 52 communicates with the upper end of the cylinder 82 throughthe medium of a passage 5d in the manner clearly shown in Figure 4. The piston is moved to the position shown in Figure 3 against the action of a spring 55-so that releasingv of the control element ill by the operator returns the piston to its outermost position relative to the cylinder wherein the exhaust passageSt is uncovered by the piston permitting fluid to escape from the cylinder 82 through the exhaust port 57. A drop in pressure in the cylinder l2 above the piston permits the shoulder 59 on the upper end of the stud, whereupon continued upward movement of the piston under the action of the spring 31 effects a swinging movement of the electrode 29 away from the electrode l5. The lost motion provided in moving the electrode 29 out of engagement with the work is for the purpose of insuring opening of the circuit to the electrodes before the work is disengaged by the electrodes.

Referring again to Figure 3 of the drawings, it will be noted that the piston 50 is provided with an insert 60 of a suitable insulating material, and this insert is axially bored to receive a stud ill; The outer end of the stud is threaded to provide for attaching the control element 5| theretothe stud to the piston 50. A cage or retainer 64 is threaded on the enlarged head 63 of the stud and is provided with a radially inwardly extending flange 65 forming an abutment for an enlargement 66 on a switch contact carrying plunger iii. The enlargement 66 on the plunger 67] is normally urged into engagement with the flange 65 by means of a coil spring 68 housed in the retainer with the opposite ends respectively engaging the stud and plunger. The plunger 61 is provided with spaced contact members 89 adapted to engage cooperating stationary contact elements ill to complete a welding circuit through the electrodes and to also close the circuit to the motor 24 through the solenoid lit. The general arrangement is such that continued movement of the valve piston 58 from the position thereof shown in Figure 3 closes the circuit to the motor 26 to drive the electrode l5 and also closes the welding circuit to the electrodes.

Operation Assuming that the parts of the apparatus are in a position wherein the electrode 29 is spaced from the electrode l5, it will be noted that initial movement of the control element 50 by the'operator-against the action of the spring 55 establishes communication between the source of fluid under pressure and the upper end of the cylinder l2. This communication is established before the switch contacts 69 are moved into engagement with the cooperating switch contacts 10 so that thepiston 35 is moved downwardly to effect movement of the electrode 29 into engagement with the work prior to closing :the circuit to the electrodes. Continued movement of the control element 58 causes the switch contacts 69 to engage the cooperating switch contacts [0 to complete the circuit to the motor 24 and to also complete the welding circuit to the electrodes. Closing of the circuit to the motor 24, of course, effects a positive drive of the electrode 65 and assists in moving the welder along the work to be welded together.

When the weld has been completed, the control 5i is released permitting the spring 55 to open I the welding circuit and the circuit to the motor 2 3, During this return movement of the control 5i, the piston valve 5h closes the fluid pressure intake port 53 and opens the exhaust passage 56 after the circuit to theelectrodes has been discontinued. Exhausting the pressure from the cylinder !2 permits the spring 3'! to move the piston 36 into engagement with the shoulder 58 on the stud 2d and raise this stud the extent necessary to swing the electrode 29 out of engagement with the work.

What we claim as our invention is:

1. In welding apparatus, a pair of electrodes arranged in an electrical circuit and supported for relative movement toward and away from each other, one of the electrodes being in the form of a roll, fluid pressure operated means for relatively moving the electrodes toward each other into clamping engagement with the work to be welded, an electric motor arranged in an electric circuit and operatively connected to said roll for driving the latter, and valve means for controlling the fluid pressure operated means and having provision for closing the motor circuit in timed relation to admitting fluid pressure to said fluid pressure operated means.

2. In welding apparatus, a pair of electrodes arranged in an electrical circuit and comprising opposed rolls supported for relative movement toward and away from each other, fluid pressure operated means for relatively moving the rolls toward each other into clamping engagement with the work to be welded, an electric motor arranged in an electric circuit and operatively connected to one of the rolls for driving the latter, and valve means for controlling the fluid pressure operated means and having provision for closing both-the motor circuit and electrode circuit in timed relation to relative movement of the electrodes into engagement with the work.

3. In welding apparatus, a pair of electrodes arranged in an electrical circuit and comprising opposed rolls supported for relative movement toward and away from each other, fluid pressure operated means for relatively moving the rolls toward each other into clamping engagement with the work to be welded, a switch in the electrode circuit, valve means for controlling the fluid pressure operated means and including a plunger movable in one direction'to successively admit fluid pressure to said fluid pressure operated means and close said switch, and an electric motor operatively connected to one of the rolls for driving the same and rendered operative by said plunger upon movement of the latter in the direction aforesaid.

4. In welding apparatus, a frame having a hub, a spindle rotatably supported in the hub and having a roll secured thereto forming an electrode, an arm pivotally mounted on the frame and carrying a revoluble roll forming a second electrode movable by the arm toward and away from the first electrode, fluid pressure operated means connected to the arm for swinging the latter in a direction to move the second roll toward the first roll, and valve means also carried by the frame and controlling said fluid pressure operated means.

5. In welding apparatus, a frame having a hub, a spindle rotatably supported in the hub and having a roll secured thereto forming an electrode, an arm pivotally mounted on the frame and carrying a revoluble roll forming a second electrode movable by the arm toward and away from the first electrode, fluid pressure operated means connected to the arm for swinging the latter in a direction to move the second roll toward the first roll, an electric circuit for the electrodes, 2. switch in said circuit, valve means controlling the fluid pressure operated means and having provision for successively admitting fluid pressure to the fluid pressure operated means and closing said switch, and means rendered operative by said valve means to drive one of said rolls.

6. In welding apparatus, a pair of electrodes arranged in an electric circuit and supported for relative movement toward and away from each 1 other, one of the electrodes being in the form of a roll, means for relatively moving the electrodes towardeach other into engagement with opposite sides of a work piece, means for closing the circuit to the electrodes in timed relation to relative movement of the electrodes into engagement with the work, power driven means oper- JOHN EDWARD MCINTOSH. HAROLD UREN.

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